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Employee Postretirement Benefits - Schedule of One-percentage-point Change in Assumed Health Care Cost (Detail)
$ in Millions
12 Months Ended
Dec. 31, 2016
USD ($)
Defined Benefit Plan Disclosure [Line Items]  
Effect on net periodic benefit cost - Increase $ 0.2
Effect on net periodic benefit cost - Decrease (0.2)
Assumed One-percentage-point Change [Member]  
Defined Benefit Plan Disclosure [Line Items]  
Effect on PBO - Increase 4.9
Effect on PBO - Decrease $ (4.2)